The Marine Mammal Center is tracking a harbor seal’s movements in the Pacific Ocean, with the help of seven satellites orbiting the earth.

Agaptimoss, a six-month old Pacific harbor seal pup, was rescued in June on a Monterey Bay beach, looking weak and underweight. Beachgoers were approaching him closely, which is never a good idea because humans and dogs can cause a wary mother to abandon her pup before it’s old enough to survive on its own. These animals naturally haul out on land to rest, so you don’t want to interrupt them. He was found on a beach between Aptos and Moss Landing, which is how he got his unusual name.

The initial Distressed Animal Report on Agaptimoss described his behavior as aware, but with “no flight response.” He was reported to be “flat down,” with one eye open. Together with watery eyes, this was an early indication of possible visual problems. After he was transported to Sausalito and examined at the Center’s hospital, he was found to have cataracts and to be blind in one eye. In their assessment of Agaptimoss, veterinary technicians reported the “retinal degeneration is likely either congenital in nature or secondary to an in utero infection.”

Agaptimoss responded well to treatment during the 11 weeks he was at the Center. At first, it was uncertain if he would be fit to be released, considering his visual problems. After initial tube feedings, he was put on a regimen of whole fish, which he quickly learned to find at the bottom of the pool rather than on the surface. He seemed to have sensitivity to light, which may have made it easier for him to find the fish in the darker depths of the pool.

Part of the treatment for Agaptimoss was to teach him how to forage and fend for himself in the wild. With the help of the UC Davis bio-engineering lab, an “enrichment box” was constructed to stimulate a seal’s natural curiosity and aptitude to search for food. The box was filled with fish and placed in the bottom of the pool that Agaptimoss shared with his two harbor seal roommates, Ranger Luke and Lira, who were also being prepared for release. Having the box at the bottom of the pool was an important part of the training, as it teaches the animals to forage while holding their breath, something they don’t learn when fish is simply dumped into the pool.

Agaptimoss, in spite of being blind in one eye, was the first of the three of them to find the box and start nudging it with his nose to open the slat and retrieve the fish. The box is designed so the top cover will close by itself as soon as the animal moves away, so he will have to make an effort every time to get a fish. Agaptimoss learned quickly how to get the fish from the box, demonstrating that he could survive in the wild on his own.

Agaptimoss doubled in size during his 11-week stay at the Center, going from 25 to 50 pounds. His healthy appetite, quick learning behavior, and a final exit exam that included a “live fish test” qualified him to be released back to his natural home in the ocean. Before his release, Agaptimoss was fitted with a satellite tracking tag, which is transmitting data back to The Marine Mammal Center, allowing the staff to assess his location and behavior. The tag was attached to his head using a strong adhesive, although it is only temporary and will fall off when he molts.

Soon after the tracking tag was attached to Agaptimoss, data started to come in to the Center. It is smart enough to determine if he is “wet” or “dry,” indicating how much time he spends swimming in the ocean or hauled out on land. The accumulation of data slowly built a map of his progress that began with a voyage by truck from The Marine Mammal Center in the Marin Headlands to the Monterey Peninsula. The location information is not transmitted continuously, but rather every few hours, so the route is shown by connecting the dots of each transmission. This produces a map that displays his voyage in a straight line, rather than following the route of Highway 101. This can be deceiving, as it appears that the truck somehow took a shortcut directly across Monterey Bay!

The map on the left shows the journey by truck from The Marine Mammal Center to Cypress Point, while the map on the right shows the movement of Agaptimoss since his release, with data points that are generated every few hours

The map data is useful in showing the movement of Agaptimoss since his release on September 5 at Cypress Point on the Monterey Peninsula. Like the journey by truck, the lines have to be read as travel between two points; not necessarily a direct route. Agaptimoss made his way around the Monterey Peninsula and back to his old stomping grounds near Moss Landing, although the map shows him traveling directly across the peninsula, through the streets of Monterey and Pacific Grove. For all our technological advancements in the 21st century, keeping tabs on a half blind harbor seal can still be a challenge.